Short Selling: The Impact of SEC Rule 201 of 2010

Despite its sizeable compliance costs, we are unable to document any clear benefits of SEC Rule 201 in ensuring fair valuations and price stability, promoting higher liquidity and execution quality, or preventing a sudden flash crash or prolonged market crises. Our daily and intraday analysis of data both before and after Rule 201 finds that short sellers are naturally more active before the occurrence of negative returns, not after significant price declines. Our simulation results show that Rule 201 further curtails short selling during normal periods, but is not binding on short sellers during the volatile period of the 2008 financial crisis.     

卖空威胁能提升企业创新吗？——基于融券交易的准自然实验

卖空威胁作为资本市场的压力,对企业创新具有重要影响。本文利用2007-2018年国内上市公司数据,依托融券制度为准自然实验,基于双重差分法探讨卖空威胁与企业创新之间的关系,检验高管团队职能经验异质性和行业市场竞争环境对上述关系的调节效应,并进一步考察卖空威胁的作用机制。结果表明,卖空威胁显著提升企业创新水平;高管团队职能经验异质性会强化卖空威胁与企业创新的正向关系,而行业竞争性则会弱化上述关系;卖空威胁影响企业创新的机制不仅包括公司治理机制,还包括信息机制。此外还发现了卖空威胁对提升成熟期的企业和国有企业的创新水平更为明显。本文结论丰富了企业创新前因性研究体系,更为企业在卖空威胁下的创新决策提供重要的借鉴。     

Tax Competition,Investment Irreversibility and the Provision of Public Goods

This article studies the effects of tax competition on the provision of public goods under business risk and partial irreversibility of investment. As will be shown, the provision of public goods changes over time and also depends on the business cycle. In particular, under source‐based taxation, in the short term, public goods can be optimally provided during a downturn. The converse is true during a recovery: in this case, they are underprovided. In the long term, however, tax competition does not affect capital accumulation. This means that the provision of public goods is unaffected by taxation.     

TRIPs约束下的国际技术转移

《与贸易相关的知识产权协议》的签订一定程度上强化了发展中国家的知识产权保护，使技术的国际转移更多地通过贸易而非FDI的形式进行，同时，也使发展中国家的短期静态收益受损，充分利用TRIPs中的一些条款是发展中国家发展本国技术能力的重要条件。     

企业短期偿债能力分析

短期偿债能力分析是企业财务分析中一个重要组成内容。现有评价企业短期偿债能力的指标有流动比率、速动比率等,这些财务指标能够较好地发挥分析评价作用,但使用这些指标的过程中也存在一些问题。为了提高企业偿债能力,分析了偿债能力分析中存在的问题,并提出了一些改进和建议。     

短生命周期产品的订货与翻新库存决策模型

文章对短生命周期产品的销售商订货与翻新决策问题进行研究。假定产品的需求和售价随时间而下降,销售商仅在销售周期之初订货一次,九许顾客退货,退货服从泊松分布且定期进行翻新,翻新品作为服务性产品满足顾客的需求,未翻新的退货在销售周期末被处置,构建了订货与翻新库存决策模型,得到了期望平均利润函数,并给出了期望平均利润函教取最大值的条件及确定决策变量的求解方法。最后,对于具体例子,得到了最优的订货与翻新策略。参数影响表明,通过降低订货、翻新和处置的固定成本与变动成本以及服务性产品与退货单位时间的持有成本、确定合适的订货量或者提高期初产品售价等措施将有助于提升期望平均利润。     

三相异步电动机的保护

本文阐述了三相异步电动机的短路、过载、欠电压、缺相保护的原因、产生的后果及具体保护办法。     

浅谈110kV变压器抗短路能力的措施

110kV变压器抗短路能力的增强措施很多,文章介绍了目前我国电力技术设备发展中,经过实践验证的七项强化措施,主要从技术、工艺两个角度阐述针对变压器抗短路能力的有效措施,并提出了几点并不成熟的措施介绍,以供业内人士的思考。     

Investment and Arbitrage Opportunities with Short Sales Constraints

In this paper we consider a family of investment projects defined by their deterministic cash flows. We assume stationarity—that is, projects available today are the same as those available in the past. In this framework, we prove that the absence of arbitrage opportunities is equivalent to the existence of a discount rate such that the net present value of all projects is nonpositive if the projects cannot be sold short and is equal to zero otherwise. Our result allows for an infinite number of projects and for continuous as well as discrete cash flows, generalizing similar results established by Cantor and Lippman (1983, 1995) and Adler and Gale (1997) in a discrete time framework and for a finite number of projects.     

Equilibria in incomplete assets economies with infinite dimensional spot markets

The paper studies the two period incomplete markets model where assets are claims on state contingent commodity bundles and there are no bounds on portfolio trading. The important results on the existence of equilibrium in this model assume that there is a finite number of commodities traded in each spot market and that preferences are given by smooth utility functions. With these assumptions an equilibrium exists outside an “exceptional” set of assets structures and initial endowments. The present paper extends these results by allowing for general infinite dimensional commodity spaces in each spot market. These include all the important commodity spaces studied in the literature on the existence of Walrasian equilibrium—in each spot market the consumption sets are the positive cone of an arbitrary locally solid Riesz space or of an ordered topological vector space with order unit or of a locally solid Riesz space with quasi-interior point. The paper establishes that even with our very general commodity spaces there exists an equilibrium for a “very” dense set of assets structures. Our approach is in the main convex analytic and the results do not require that preferences be smooth or complete or transitive. The concepts and techniques studied in this paper have important finite as well as infinite dimensional applications. This paper has benefited from the comments of Martine Quinzii, Wayne Shafer, Manuel Santos and Yeneng Sun. The research of C. D. Aliprantis is supported by the NSF Grants SES-0128039, DMS-0437210, and ACI-0325846. The research of R. Tourky is funded by the Australian Research Council Grant A00103450.